1. Field of the Invention
The present invention relates to a communication device, a method, and a computer program product. The communication device transmits information to and receives information from a computer running a virtual machine.
2. Description of the Related Art
Conventional technology allows a communication device, which is connected to a calculating device via a network, to display screen data displayed on the calculating device. The technology allows processes performed by the calculating device to be controlled.
A following system is realized through the use of the above-described technology. A user carries a communication terminal device having only a minimal input and output interface, such as a liquid crystal touch-panel and a pen. The communication terminal device connects over a network to a server (calculating device) present at a remote location. The communication terminal device uses a service provided by the server.
In recent years, a technology has been proposed to make a plurality of virtual machines run on a server. A virtual machine allows a physical computer to run a plurality of virtual computers, mainly through use of software, and allows the virtual computers to run operating systems and application programs. As a result, a system conventionally operated by many computers can be implemented by fewer computers.
When a virtual machine technology is applied to the above-described system, a server that is a connection destination of the communication terminal device is transferred, for example, from a virtual machine server A to a virtual machine server B, according to user operation.
When a system using the virtual machines such as that above is run, it is preferable to make the server which operates the virtual machines stop a virtual machine not currently used by, for example, the communication terminal device as long as possible because such operation directly leads to improvement in service scalability.
On the other hand, when the communication terminal device resumes use of a service provided by a virtual machine that has been stopped, the user is required to wait while the virtual machine is being restarted. Therefore, when the virtual machine provides a service, a judgment regarding when to stop operation of the virtual machine is required to be carefully made.
In an online article entitled “Suspending and Resuming Virtual Machines”, a technology is proposed that allows stopping and starting of a virtual machine to be changed depending on a user. According to this technology, the user can change when to stop and start the virtual machine Therefore, the user can control the virtual machine so as to make the virtual machine stop after the use and make the virtual machine start in advance when the user wishes to use the virtual machine.
However, though the technology described in “Suspending and Resuming Virtual Machines” allows the user to indicate when to stop the virtual machine, it is not easy for the user to appropriately determine whether to stop the virtual machine or not.